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Chinese Journal of Chemistry 2024年第6期42卷 592-598页

作者： Yin Zhang wei-dong yu Fang-Qian Wang Xiangnan Wang Jiawan Zhou Chao Liu Jun Yan Junior Education Department Changsha Normal UniversityChangshaHunan410100 China School of Science Hunan University of Technology and BusinessChangshaHunan410000 China College of Chemistry and Chemical Engineering Central South UniversityChangshaHunan410000 China

Polyoxometalates modified with complex cations have attracted increasing attention because of the fascinating properties and the controllable *** adjusting the synthesis conditions,four new terpyridine complexes based hybrid POMs,[(TPY-H)CuCl]_(4)[W_(10)O_(32)]·2DMF·2H_(2)O(1),[(TPY-H)Cu(DMSO)(H_(2)O)]_(2)[W_(10)O_(32)]·2H_(2)O(2),[(TPY-H)_(2)Cu]_(2)[W_(10)O_(32)]·6DMSO·8H_(2)O(3) and[(TPY-Br)CuCl(DMSO)(H_(2)O)]_(2)[(TPY-Br)CuCl]_(2)[W_(10)O_(32)]·2DMSO·4H_(2)O(4),were prepared by using‘one-pot’***-crystal X-ray diffraction analyses,infrared radiation,etc.,revealed the structural composition of compounds 1—4,which indicates that synthesis conditions have a directional regulatory effect on the compounds *** oxidation catalytic reactions show 1—4 have good catalytic activities,and powder X-ray diffraction and thermogravimetry analysis show 1—4 have superduper catalytic ***,4 has better catalytic activity because of the different structure of terpyridine ***,a possible mechanism of dual-site catalysis by both cations and anions is proposed.

关键词： Polyoxometalates Terpyridine complexes Thioether oxidation Dual-site catalysis Clusters

多巴胺改性聚二乙炔复合热致变色材料的制备及性能

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高分子学报 2024年第4期55卷 428-437页

作者：刘浩谭家玲于伟东刘佳音王潮霞江南大学纺织科学与工程学院无锡214122

聚二乙炔变色温度较高且受热构象转变后难以回复,可通过端基改性赋予其热致变色可逆的性能并改变变色温度,以适合应用在人体温度智能传感方面.采用多巴胺改性二乙炔形成分子间氢键,二乙炔头基处多巴胺聚合形成共价键,254 nm紫外光照形... 详细信息

聚二乙炔变色温度较高且受热构象转变后难以回复,可通过端基改性赋予其热致变色可逆的性能并改变变色温度,以适合应用在人体温度智能传感方面.采用多巴胺改性二乙炔形成分子间氢键,二乙炔头基处多巴胺聚合形成共价键,254 nm紫外光照形成双聚合体系(Poly-PCDA-PDA),且将改性二乙炔与热塑性聚氨酯(TPU)进行复合.改性后聚二乙炔相转变点由62℃降低至约39℃,热致变色温度为35℃且能够在蓝-紫相之间发生完全可逆转变,改性二乙炔与TPU的复合制备了稳定性高且能够发生可逆热致变色的薄膜,更符合人体温度环境应用场景.提供了一种多巴胺取代头基后通过共价键连接进一步改性聚二乙炔的策略,有望在聚二乙炔基人体温度传感材料的研究中起到重要作用.

关键词：热致变色聚二乙炔多巴胺聚氨酯自组装

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浅析医疗设备维修与质量控制的结合与应用

中国医疗器械信息 2024年第9期30卷 161-164页

作者：魏瑜栋王聪颖潍坊医学院附属医院招标办公室山东潍坊261300 潍坊市人民医院医学装备部山东潍坊261300

随着现代医疗事业的不断持续发展,医疗设备也迎来了发展的又一契机,这对国内的医疗单位而言,既是一种艰巨的挑战,也是一个发展的机遇。当下,如果想提高医疗单位的整体医疗质量,升级和优化医疗设备与流程必不可少,而要想实现升级和优化目... 详细信息

随着现代医疗事业的不断持续发展,医疗设备也迎来了发展的又一契机,这对国内的医疗单位而言,既是一种艰巨的挑战,也是一个发展的机遇。当下,如果想提高医疗单位的整体医疗质量,升级和优化医疗设备与流程必不可少,而要想实现升级和优化目标,就必须严格管理好医疗单位的相关医疗设备,并对其进行精细化的维护。因此,探析医疗机构医疗设备在维修管理中存在的问题,并有针对性地对其存在问题提出具体的维护措施和保养措施,对提高我国医疗设备的管理水平具有十分重要的现实意义。

关键词：多元合作模式医疗设备维修管理管理措施

Research on the novel asymmetric frequency division duplex technique

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The Journal of China Universities of Posts and Telecommunications 2006年第4期13卷 13-18页

作者： ZHANG Ying-hai WANG wei-dong dong yu ZHOU Kai-Jie Information and Electronics Technology Laboratory Beijing University of Posts and Telecommunications Beijing 100876 China

This article introduces a novel duplex transmission technique-asymmetric frequency division duplex （AFDD）. One of the characteristics in future mobile systems is asymmetric characteristic caused by service requirement and electromagnetic radiation, AFDD is designed to adapt to the new asymmetric characteristics. The AFDD puts forward a novel adaptive frequency-allocation scheme in downlink and uplink. Combining AFDD with code division multiple access （CDMA） communication system, it is proven that AFDD improves the capacity and coverage of the system compare with FDD CDMA system.

关键词： asymmetric characteristics AFDD Duplex Mobile communications

Dimensional Reduction of Eu-Based Metal-Organic Framework as Catalysts for Oxidation Catalysis of C(sp^(3))-H Bond

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Chinese Journal of Chemistry 2022年第4期40卷 480-486页

作者： Yin Zhang wei-dong yu Cai-Feng Zhao Jun Yan Junior Education Department Changsha Normal UniversityChangshaHunan 410100China College of Science Hunan University of Technology and BusinessChangshaHunan 410000China College of Chemistry and Chemical Engineering Central South UniversityChangshaHunan 410000China Hunan Institute of Nuclear Agricultural Science and Space Breeding Hunan Academy of Agricultural ScienceChangshaHunon 410000China

Comprehensive Summary Developing new catalysts for highly selectivity and conversion of saturated C(sp^(3))-H bonds is of great *** order to obtain catalysts with high catalytic performance,six Eu-based MOFs with different structural characteristics were obtained by using europium ions and different organic acid ligands,namely Eu-1~***-1,Eu-2 and Eu-3 featured three-dimensional structures,while Eu-4 and Eu-5 featured two-dimensional structures.

关键词： Metal-organic frameworks Heterogeneous catalysis Rare earths Dimensional reduction Selectively oxidize C(sp^(3))-H

Major complications after radiofrequency ablation for liver tumors:Analysis of 255 patients

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World Journal of Gastroenterology 2009年第21期15卷 2651-2656页

作者： Wen-Tao Kong wei-wei Zhang yu-dong Qiu Tie Zhou Jun-Lan Qiu wei Zhang Yi-Tao Ding Department of Hepatobiliary Surgery Drum Tower Hospital Medical College of Nanjing University Nanjing 210008 Jiangsu Province China

AIM:To investigate the major complications after radiofrequency ablation(RFA) for the treatment of liver tumors and analyze possible risk factors that precipitate these ***:From March 2001 to April 2008,255 patients with liver tumors(205 male,50 female;age range,18-89 years;mean age,56.0 years) who received RFA were enrolled in this *** these patients,212 had hepatocellular carcinoma,39 had metastatic liver tumors and four had cholangiocellular *** hundred and forty eight patients had a single tumor,and 107 had multiple *** diameter of the tumors ranged 1.3-20 cm(mean,5.1 cm).All patients were treated with a cooled-tip perfusion electrode attached to a radiofrequency generator(Radionics,Burlington,MA,USA).RFA was performed via the percutaneous approach(n = 257),laparoscopy(n = 7),or open surgical treatment(n = 86).The major complications related to RFA were *** resultant data were analyzed to determine risk factors associated these ***:Among the 255 patients,425 liver tumors were treated and 350 RFA sessions were ***-seven(10%) major complications were observed which included 13 cases of liver failure,10 cases of hydrothorax requiring drainage,three casesof tumor seeding,one case of upper gastrointestinal bleeding,one case ofintrahepatic abscess,one case of bile duct injury,one case of cardiac arrest,and five cases of *** patients had more than two *** failure was the most severe complication and was associated with the highest *** patients died due to worsening liver ***-Pugh classification(P = 0.001) and choice of approach(P = 0.045) were related to post-treatment liver failure,whereas patient age,tumor size and number were not significant factors precipitating this ***:RFA can be accepted as a relatively safe procedure for the treatment of liver ***,attention should be paid to possible com

关键词： Complication Hepatocellular carcinoma Metastatic liver tumor Radiofrequency ablation Liverfailure

Effect of Microstructure on Corrosion Fatigue Behavior of 1500 MPa Level Carbide-Free Bainite/Martensite Dual-Phase High Strength Steel

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Journal of Iron and Steel Research International 2011年第4期18卷 63-67页

作者： XU Lei wei dong-yuan yu Yang ZHANG Han BAI Bing-zhe Laboratory of Advanced Materials Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

Influence of microstructure of the experimental steels on the corrosion fatigue behavior in 3.5% of NaCl aqueous solution was *** results show that compared with the full martensite（FM）steel,the carbide-free bainite/martensite（CFB/M）steel has higher corrosion fatigue strength and corrosion fatigue crack threshold（ΔKthcf）,and lower corrosion crack propagation rate [（da/dN）cf].

关键词： high strength steel carbide-free bainite/martensite dual-phase steel corrosion fatigue

Fusobacterium nucleatum promotes colon cancer progression by changing the mucosal microbiota and colon transcriptome in a mouse model

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World Journal of Gastroenterology 2022年第18期28卷 1981-1995页

作者： Na Wu yu-Qing Feng Na Lyu Di Wang wei-dong yu Yong-Fei Hu Department of Central Laboratory&Institute of Clinical Molecular Biology Peking University People’s HospitalBeijing 100044China State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

BACKGROUND Fusobacterium nucleatum(***)has long been known to cause opportunistic infections and has recently been implicated in colorectal cancer(CRC),which has attracted broad ***,the mechanism by which it is involved in CRC development is not fully *** To explore its potential causative role in CRC development,we evaluated the colon pathology,mucosa barrier,colon microbiota and host transcriptome profile after *** infection in an azoxymethane/dextran sulfate sodium salt(AOM/DSS)mouse *** Three groups of mice were compared to reveal the differences,i.e.,the control,AOM/DSS-induced CRC and AOM/DSS-FUSO infection *** Both the AOM/DSS and AOM/DSS-FUSO groups exhibited a significantly reduced body weight and increased tumor numbers than the control group,and AOM/DSS mice with *** infection showed the highest tumor formation ratio among the three ***,the colon pathology was the most serious in the AOM/DSS-FUSO *** found that the structure of the colon microbiota changed considerably after *** infection;striking differences in mucosal microbial population patterns were observed between the AOM/DSS-FUSO and AOM/DSS groups,and inflammation-inducing bacteria were enriched in the mucosal microbiota in the AOM/DSS-FUSO *** comparing intestinal transcriptomics data from AOM vs AOM/DSSFUSO mice,we showed that transcriptional activity was strongly affected by dysbiosis of the gut *** most microbiota-sensitive genes were oncogenes in the intestine,and the cyclic adenosine monophosphate signaling pathway,neuroactive ligand–receptor interaction,PPAR signaling pathway,retinol metabolism,mineral absorption and drug metabolism were highly enriched in the AOM/DSS-FUSO ***,we showed that microbial dysbiosis driven by *** infection enriched eight taxa belonging to Proteobacteria,which correlates with increased expression of oncogenic *** Our

关键词： Fusobacterium nucleatum Mucosal microbiota Transcriptome Colorectal cancer Inflammation-inducing bacteria

Synergistic Brønsted Base/Photoredox-Catalyzed Three-Component Coupling with Malonates to Synthesize δ-Hydroxy Esters and δ-Keto Esters

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Chinese Journal of Chemistry 2024年第9期42卷 957-962页

作者： Ting Li wei Wang Ming dong Zhije Zhang Sha yu Zhengchu Chen Siping wei dong Yi Green Pharmaceutical Technology Key Laboratory of Luzhou City Central Nervous System Drug Key Laboratory of Sichuan ProvinceSchoolof PharmacySouthwestMedicalUniversityLuzhouSichuan 646000China Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province LuzhouSichuan 646000China

Multicomponent alkene 1,2-dicarbofunctionalizations(DCFs)have emerged as a powerful strategy to rapidly incorporate both two carbon subunits across one C-C double bond in one step for enhancing molecular complexity and *** the best of our knowledge,there is only one report on photoredox-catalyzed three-component DCFs with malonates through the radical−radical cross-coupling,while photoredox-catalyzed radical-polar crossover(RPC)-type DCFs with malonates were still ***,we describe a redox-neutral RPC-type 1,2-dialkylation of styrenes with malonates and aldehydes through the synergistic Brønsted base/photoredox catalysis *** transition-metal-free strategy provides an efficient and clean approach to a broad variety ofδ-hydroxy esters and also features exceptionally mild conditions,wide compatibility of substrate scope and functional groups,and high atomic ***,three-component 1,2-alkylacylation from the same starting materials was achieved in one-pot manner through such RPC-type coupling and subsequent two-electron oxidation process,providing a set ofδ-keto esters of interest in pharmaceutical research.

关键词： Alkene difunctionalization Photoredox catalysis Malonates Radical reactions C-C coupling Synthetic methods Aldehydes Alkylation Multicomponentreactions

Drinking water quality & health risk assessment of secondary water supply systems in residential neighborhoods

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 47-62页

作者： Yating wei dong Hu Chengsong Ye Heng Zhang Haoran Li Xin yu College of the Environment&Ecology Xiamen UniversityXiamen 361102China School of Public Health Shandong First Medical University&Shandong Academy of Medical SciencesJinan 250117China

Secondary water supply systems(SWSSs)are important components of the water supply infrastructure that ensure residents’drinking water *** are characterized by long detention time,warm temperature,and unreasonable management,which may trigger the deterioration of water quality and increase *** this study,drinking water quality index(DWQI)and health risk assessment(HRA)were selected and modified to quantitatively assess the water quality and health risks of SWSSs in residential *** total,121 seasonal water samples were *** was observed that the water quality was excellent with the DWQI of 0.14±0.04,excluding one sample,which was extremely poor owing to its excessive total bacterial *** HRA results revealed that the health risks were low:negligible non-carcinogenic risk for any population;negligible and acceptable carcinogenic risk for children aged 6–17 and ***,samples revealed higher carcinogenic risk(7.63×10−5±3.29×10−6)for children aged 0–5,and arsenic was the major *** samples had poor water quality and higher health risks,which called for *** further investigate the water quality and health risks of SWSSs,monthly sampling was conducted during *** 24 water samples were qualified in Chinese standard(GB 5749-2022)and characterized as excellent *** HRA results were consistent with the seasonal samples’and the health risks were mainly concentrated in ***,our study provides a suitable framework for water quality security,advice for managers,and references for administrators in other cities.

关键词： Drinking water quality Water quality index Health risk assessment Secondary water supply systems Heavy metals